import os
import sqlalchemy
from sqlalchemy import create_engine, column, integer, string, foreignkey, sequence
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, relationship
"""backref='addresses' #直接使用表名
backref = backref('address')
backref = backref('address', order_by=id)
"""base_dir = os.path.abspath(os.path.dirname(__file__))
db_path = os.path.join(base_dir, 'data.one.many.sqlite')
engine = create_engine('sqlite:///' + db_path, echo=true)
base = declarative_base()
session = sessionmaker(bind=engine)
session = session()
class user(base):
__tablename__ = 'users' # user類對映到users表
id = column(integer, sequence("user_id_seq"), primary_key=true) # sequence表示id自增長, 主鍵 name = column(string)
fullname = column(string)
password = column(string)
def __init__(self, name, fullname, password):
self.name = name
self.fullname = fullname
self.password = password
def __repr__(self):
return "< user (name = '%s', fullname='%s', password='%s')>" %( self.name, self.fullname, self.password )
class address(base):
__tablename__ = 'addresses' # address類對映到addresses表
#id = column(integer, primary_key=true)
id = column(integer, sequence("user_id_seq"), primary_key=true) # sequence表示id自增長, 主鍵
email_address = column(string, nullable=false)
user_id = column(integer, foreignkey('users.id')) # 多對一。此表的外來鍵就是 users表中的主鍵，id.多個address屬於乙個user
user_view = relationship("user", back_populates='addresses') # 使用者和位址關係表，沒有實際資料庫表，只是乙個關係對照表
def __init__(self,email_address):
self.email_address = email_address
def __repr__(self):
return "" % self.email_address
user.addresses = relationship("address", order_by=address.id, back_populates="user_view") # 在user類中增加乙個位址屬性，指向位址的對照表
base. metadata.create_all(engine)
#使用zhangsan = user('zs','zhangsan', 'abc222') # 設定使用者名稱
lisi = user('ls','lisi', '123456')
# 使用者郵址
zhangsan.addresses = [
address(email_address="[email protected]"),
address(email_address="[email protected]"),
]lisi.addresses = [
address(email_address="[email protected]"),
address(email_address="[email protected]"),
]session.add_all([zhangsan, lisi])
session.commit()
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